Portable oil well derrick



Dec. 9 1958 H. J. wooLsLYER Erm. 2,863,530

-PQRTBLE OIL WELL. DERRICK Filed Feb. 3. 1954 hlffil..

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wLv/N 4. BY dm., f1/w, JM 02%@ States atet 2,863,530 Patented Dec. 9, T958 PURTABLE UIL WELL DERRICK Homer il. Woolslayer, Cecil Jenkins, and Calvin L. Turner, Tulsa, Okla., and Erwin A. Campbell, Wexford, Pa., assignors to Lee C. Moore Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application February 3, 1954, Serial No. 407,906

Claims. (Cl. 189-l1) This invention relates to portable oil well derricks, and more particularly to those that are swung up to upright position with the help of a gin pole.

The usual practice in raising a portable oil well drilling derriclc is to swing a mast up to erect position, where it is supported by the gin pole that helped raise it. The gin pole generally is of A frame construction; that is, its front and rear sides are hinged together at the top and diverge downwardly, with the lower end of the front side hinged to the base at the foot of the mast and with the lower end ot the back side detachably connected with the base a considerable distance behind the foot of the mast to provide as much clear working space as possible. The gin pole can be folded and swung forward onto the reclining mast for transportation. The size and weight of such a gin pole are important factors in handling it, and adequate strengthening of the front of the gin pole, which is under compression during raising of the mast, becomes more of a problem as the gin pole in increased in height. Therefore, since the height of the gin pole is limited by practical considerations, the size of the A frame opening in the lower portion of the derrick also is limited.

It is among the objects of this invention to provide an oil well derrick in which the mast is supported in upright position independently of the gin pole, in which the size of the A frame opening in the lower portion of the derrick is independent of the size of the gin pole, in which the gin pole can be used to help brace the erected derrick, in which snubbing of a gin pole during its erection is eliminated, and with which the driller standing beside the drawworks enjoys greater visibility than heretofore.

ln accordance with this invention a reclining mast has a head and a foot which is hinged to a base, from which the mast extends forward. A line extends from a traveling block in the mast to the head of the mast and then back over the base to drawworks on the base. When the line is reeled in by the drawworks, it pulls the traveling block toward the head of the mast in a well known manner. Secured to the top of the reclining mast a considerable distance from its foot is a prop which is inclined upward and backward therefrom. A gin pole is supported by the base adjacent the foot of the mast and extends upward. A line is connected to the upper end of the pole and extends forward into the mast, where it is connected to the traveling block. Consequently, when the block is pulled toward the head of the mast the latter is swung upward and backward until it is erect. In the erect position the lower end of the prop is supported by means mounted on the base. The upper end oi the gin pole then is connected to the prop, preferably at its central portion, in order to help brace the prop. The gin pole is of simple construction and no higher than necessary for easy lifting or" the mast, but the prop extends a considerable distance above the gin pole so that a larger A frame opening can be provided than heretofore.

The preferred embodiment of the invention is illustrate-d in the accompanying drawings, in which Fig. 1 is a side view of a reclining mast about to be erected; and

Fig. 2 is a plan View thereof.

Referring to the drawings, the feet of a reclining mast 1 are pivotally mounted on hinge pins 2 in a pair of laterally spaced shoes 3 on a base 4 of any suitable construction. The mast illustrated preferably has an open lower face as is customary. Inside of the mast there is a traveling block 6 which is connected to the crown block 7 by a drilling line 3 that also extends from the crown block back over the reclining mast and a sheave 9 to the usual drawworks lll mounted on the base behind the mast.

The rear legs 12 of the mast, which are at the top of the reclining mast, have their lower or rear ends located a considerable distance from shoes 3 and are connected by inclined braces 13 to the rear ends of the front or lower legs ld. At approximately the junction of the rear legs with the inclined braces, which is called the heel of the mast, there are projecting bifurcated brackets lo, in which a pair of laterally spaced props i7 are pivotally mounted and which form continuations of the rear legs of the mast. While the mast is being moved from one location to another the props are folded down against inclined braces i3, as indicated by broken lines in Fig. l, but when the mast is to be erected the props irst are swung upward past horizontal position by any suitable means to an inclined position where they are supported by struts l. The struts may be pivotally connected to the inclined braces and detachably connected to the props. The distance from the foot of the mast to brackets i6 and the distance from the foot of the mast to the free ends or feet ig of the props are such that an unusually large triangular space is formed which will give a much greater working clearance in the base of the erected derrick than heretofore.

in order to swing the reclining mast up to erect position, a sling cable 2d is looped over the hook of the traveling block and extends backward beneath sheaves 2i journaled in opposite sides of the mast. The rear ends of the sling cable are detachably connected to the upper ends of a pair of rearwardly inclined gin poles 22, the lower ends of which are pivotally mounted in the back part or shoes 3 and in smaller shoes 23 spaced from their outer sides. The poles preferably taper upwardly. To limit the distance that the gin poles can be swung forward, tension members connect their upper ends with the base behind them. Preferably, the tension members are exible, such as cables 24 which have their lower ends anchored to the base at points behind the drawworks.

With this construction, when the drawworks drum is driven to reel in the drilling line 8, the pull of the traveling block on sling 20 toward the crown block first swings the gin poles upward and forward from the lower broken line position in Fig. l to their full line position, and then causes the mast to swing upward and back until its center of gravity passes over hinge pins 2. It then will continue to swing back by gravity until it is in upright operative position, shown in broken lines in Fig. l. This iinal movement is snubbed by a tag line (not shown) fastened to the front ot the mast. It will be seen that the props T7 travel in a path which carries them over the top of the gin poles and down to the base behind the poles.

There is no cross member connecting the tops of the gin poles, so the drilling line is free to mov-e upward between them and .back behind them as the mast is raised. In the upright position the perforated feet 19 of the props i7 are received in rear shoes 26 mounted on the base behind the front shoes, where the proper feet and rear shoes can 'be detachably connected together by drive pins (not shown). The gin poles, which are located below struts 1S, are then allowed to swing downward by lowering the traveling block until openings in forks 2-7 at the upper ends of the poles register with openings intongues 28 projecting inward from the props about midway between their opposite ends. The forks and tonguesV are then connected by removable pins 29 so that the gin poles brace the props. The sling and the tension cables 24 then are disconnected and the mast is ready to operate in the usual way.

To lower the mast, the procedure just outlined is reversed, but after the props 17 have been disconnected from the rear shoes the mast is pulled forward over center by the tag line, mentioned above, until gravity takes effect. The mast then is lowered lby paying out the drilling line 8 from the drawworks drum. After the mast reaches its lower position, the gin poles will swing downward by gravity if they are heavy enough to drag the traveling block toward the base, but in most cases it probably will be necessary to apply power to the traveling block to pull it. That can be done conveniently by means of the usual catline attached to the drawworks. As the block is pulled toward the base the sling will lower the gin poles.

It will be seen that with this construction the mast is supported in upright position by props 17 and that all that the gin poles do is to help reinforce the props. The gin poles can be limited to a size and weight convenient to handle, and yet a large A-frame opening is provided for adequate working clearance around drawworks and well. Since the gin poles are never swung over center, it is unnecessary to provide for snubbing them. Finally, in those cases where the front to back depth of the erect mast is limited, greater visibility for the driller beside the drawworks can be obtained by the increased height of the A-frame.

According to the provisions of the patent statutes we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

l. A portable oil well derrick comprising a base, a reclining mast having a head and a foot which is hinged to the base, the mast extending forward away from the base, a traveling block in the mast, a crown block at the head of the mast, a line extending from the traveling block to the head of the mast and then over the crown block and back over said base, the rear end of the line being adapted to be pulled to pull the traveling block toward the head of the mast, a prop secured to the upper' side of the reclining mast a considerable distancerfrom its foot and inclined upward and backward therefrom,

means bracing the prop in said inclined position, a gin.

pole much shorter than said prop and supported by the base adjacent the hinged foot of the mast and extending upward therefrom, tension means connecting the upper end of the gin pole with the base at the side of the pole opposite to the mast, a line connected to the upper end of the pole and extending forward into the mast for connection to the traveling block, whereby when the block is pulled toward the head of the mast the latter is swung upward and backward until it is erect, means on the base behind the gin pole for supporting the lower end of the prop when the mast is erect, and means for detachably connecting the upper end of the gin pole to said prop several feet below the upper end of the prop when the mast is erect, to thereby brace the prop.

2. A portable oil well derrick comprising a base, a reclining mast having a head and a foot which is hinged 4 to the base, the mast extending forward away from the base, a traveling block in the mast, a crown block at the head 0f the mast, a line extending from the traveling block to the head of the mast and then over the crown block and back over said base, the rear end of the line being adapted to be pulled to pull the traveling block toward the head of the mast, a pair of laterally spaced props secured to the upper side of the reclining mast a considerable distance from its foot and inclined upward and backward therefrom, means bracing the prop in said inclined position, a pair of laterally spaced gin poles hinged to the base adjacent the foot of the mast and inclined upward and backward therefrom, the gin pole being much shorter than the prop, exible tension memers connecting the upper ends of the gin poles with the base behind them, a cable sling having its opposite ends fastened to the upper ends of the gin poles and extending forward into the mast and connected to the traveling block, whereby when the block is pulled toward the head of the mast the latter is swung upward and backward and the props travel over and down behind the gin poles until the mast is erect, means on the base behind the gin poles for supporting the lower ends of said props when the mast is erect, and means for detachably connecting the upper ends of the gin poles to the central portions of said props when the mast is erect.

3. A portable oil well derrick comprising a base, a reclining four-legged mast having a head and a foot and extending forward away from the base, means hinging the rear ends of the lower legs of the reclining mast to the base, a traveling block in the mast, a crown block at the head of the mast, a line extending from the traveling block to the head of the mast and then over the crown block and back over said base, the rear end of the line being adapted to be pulled to pull the traveling block toward the head of the mast, the upper legs of the reclining mast extending from its head only part way toward said foot, a pair of laterally spaced props secured to the rear ends of said upper legs and inclined upward and backward therefrom to points above said hinging means, a gin pole supported by the base only adjacent said hinging means and extending upward therefrom, the gin pole being much shorter than the props, tension means connecting the upper end of the gin pole with the base behind the gin pole, a line connected to the upper end of the pole and extending forward into the mast for connection to the traveling block, whereby when the Iblock is pulled toward the head of the mast the props are swung upward and backward over the gin pole and down behind it until the mast is erect, and means on the base behind the gin pole for supporting the lower ends of the props when the mast is erect.

4. A derrick in accordance with claim 1, in which said tension means is flexible and the gin pole is inclined upward and rearward and has its lower end pivotally connected with the base, and including means for detachably connecting the upper end of the pole to the central portion of said prop when the mast is erect.

5. A derrick in accordance with claim 3, in which the gm pole is spaced from the mast when the mast is erect.

References Cited in the file of this patent UNITED STATES PATENTS 2,057,137 Culbertson Oct. 13, 1936 2,403,081 Hilborn July 2, 1946 2,495,563 Woolslayer et al. Jan. 24, 1950 2,505,087 Athy et al. Apr. 25, 1950 2,567,795 Woolslayer et al. Sept. 11, 1951- FOREIGN PATENTS 839,335 Germany May 19, 1952 

